The damaged stern as a result of being torpedoed by Mocenigo
On the December 13th Argonaut joined HMS Aurora, HMS Eskimo and HMS Quality and left Bone to intercept another Axis convoy however delays in setting sail meant they missed the convoy. On December 14th 1942 HMS Argonaut was hit by two torpedoes from the Italian Submarine Mocenigo and was badly damaged with both her bow and stern blown off.
Three members of her crew were killed by the explosion.
The ship made its way to Gibraltar via Algiers using only two of its four propellers. In Gibraltar a make shift bow was made which proved to be useless. The Germans were certain that the Argonaut had been sunk and reported it on German Radio. The National Savings Committee announced that the City of Coventry had raised £2,250,000 to replace the Argonaut after the announcement by the Axis.
Repairs were to take place in Philadelphia United States of America this meant crossing the U-boat infested Atlantic so on April 4th 1943 she set sail from Gibraltar with a new Commanding Officer in charge Captain Haynes RN and with her escort HMS Hero on April 7th she arrived in Ponta Delgada on the Portuguese islands of the Azores . Under the World Government Convention Ships engaged in war could shelter in Neutral ports for three days to carry out urgent repairs. When the Argonaut arrived in Ponta Delgada the ships company were surprised to see a German U-Boat along side also under going repairs. On April 8th the Argonaut set sail just a few hours after the German U-boat, HMS Hero carried out an ASW sweep and Argonaut was prepared for an attack by the U-boat but none came. HMS Hero developed problems with her engines and was detached by the Admiralty on April 9th and the Argonaut was left on her own to cross the Atlantic . On April 13th USS Butler was sighted and joined the Argonaut on her voyage. The ships reached Bermuda on April 17th after more repairs on the hull and Argonaut set sail on April 27th under the escort of USS Tumult and USS Pioneer the ships reached the port of Philadelphia on April 30th 1942.
The repairs were completed on 13 November 1943. In December 1943, Argonaut joined the Home Fleet and was attached to the 10th Cruiser Division